delaporte



- M. DELAPORTE.

DEVICE FOR INSURING STABILITY or WORKING or STEAM EJECTORS ARRANGED m sums.

AFPLlCATiON flLED "8.11, 19H.

Patented June 10, 1919.

2 SHEETS -SHEET I.

M. DELAPORTE. DEVICE FOR INSURING STABILITYWOF WORKING OF SIEAM EJECTORS ARRANGED IN SERIES. APPLICATION FILED FEB. H. 19H.

* I gg lg lutmtvdJune19,191).

2 SHEETS-SHEET 2- M c 7 J MAURICE DELALPOBTE, 0F PARIS, FOE.

DEVICE FOR :cnsuamo STABILITY or WORKING or STEAM-EJEGTORS aananenn'm SERIES.

LSQGAtM.

Specification of Letters Patent. Patented Jinn; 10, 191%} Application filed February 17, 1914. Serial No. 819,253.

To all whom it may concern:

- Be it known that I, MAURICE DELAPORTE, a citizen of the French Republic, residin at Paris, Republic of France, have invente certain new and useful Improvements in Devices for Insuring Stability of Workin of Steam-Ejecto Arranged in Series, of W iich the following is a specification.

Devices are known which are used as air pumps for extracting air from a steam condenser, and which comprise in combination steam ejectors arranged in series and used with one or more intermediate auxiliary condensers.

Devicespf the character hereinbefore referred to could not hitherto be successfully employed in practice,-either because the apparatus employed were not sufiiciently' powerful relatively to their consumption of steam, orbecause the worklng. of the ap -paratus became unstable when the proper alr pressure decreased in the condenser upon which they were working.

The bject of the present invention is to provide means, the addition of which has the effect of rendering the working. of the arrangement of steam ejectors in series used with one. or more intermediate auxiliary condensers perfectlystable, however low the roper air pressure in the condenser may be. The stability of the apparatus being thus obtained under all circumstances, e ectors ma be selected the working diagrams of which show the best eiiiciency relatively to the consumption of steam. The arrangement accordin to the present invention permits of obtaining an a1r pump, the working of which is certain and very economical.

Experiments carried out by the applicant have shown that when an ejector is suitably dimensioned so as to effect under the best conditions the extraction of a substantial quantity of gas contained in a receptacle, its operation becomes unstable when the quantity of gas that it draws is greatly decreased. The experiments have shown that in a device comprising two ejectors in series used with an intermediate auxiliary condenser, the whole working upon a steam condenser under the usual conditions, the Working of the first ejector is by itself always stable. This is due to the fact that a system of two steam ejectors in series permits of realizing the theoretical vacuum corresponding to the usual temperatures of condensers,

second ejector is concerned which can re ceive only the gases coming from the first ejector; if at any given moment these gases are almost solely constituted by steam, the latter will be condensed in the intermediate auxiliary condenser, so that the amount of gas reaching the second ejector will almost be m'l. It will thus be seen that if an air extracting device of the kind hitherto proposed operates upon a condenser in which the suppl of air is varied, the vacuum increases, t ereupon becoming unstable, when the quantity of air supplied is gradually decreased.

This instability may be overcome by a surplus in the supply of working steam to the second ejector. This, however, leads to an increase in the expenditure of working steam, and, according to the experiments which have been carried out, it decreases the extractin power of the apparatus, so that the worl ing thereof under these conditions is not economical.

The cause of the instability may also be overcome by effecting a permanent admis sion of air to the condenser; such an arrangement, however, is defective since it causes a drop in the vacuum of the condenser relatively to the obtainable theoretical vacuum, the amount of this drop bein directly proportional to the amount 0 air that has been admitted.

The invention consists in the addition to the known arrangement of steam ejectors in series used with an intermediate auxiliary condenser, of means which will allow the introduction of a supplementary amount of gaseous fluid into the gaseous mixture extracted from the condenser, the introduction of the said gaseous fluid being effected after the gaseous mixture referred to has already been subjected to a certain amount of compression in the first ejector.

Figures 1, 2, and 3 in the accompanying drawings illustrate by Way of example three diflerent Ways of carrying the invention into effect:

Referring to the arrangement illustrated in Fig. l, a is the main condenser which is steam therefor.

sures on the two sides of the valve 3 is very preferably shown as a jet condenser, the steam to be condensed entering therein at b, c is a tank containing the cooling water which is raised into the condenser through the pipe l under the action of atmospheric pressure; (Z is a centrifugal pump by which the water of condensation is drawn from the lower part of the main-condenser and delivered to the hot-water tank c. The gaseous mixture from the main condenser is drawn through a pipe f which communicates with two ejectors, a first ejector g and a second ejector h, which are arranged in series with each other and which are fed with steam through a pipe k. A small auxiliary condenser i which is preferably of the injection type is preferably interposed between the two steam ejectors, its lower end being connected with the main condenser a by means of a siphon m, the injection water being supplied at the upper end thereof through a pipe a connected with the pipe 4; the second ejector h communicates with the atmosphere through a pipe 0. Upon the suction chamber of the second ejector it is arranged a stopper 2 provided with holes 5 capable of being covered and uncovered by a movable plate 9, to any desired extent. to the position of the latter plate the quantity of air sucked into the system'is varied between any desired limits the additional air mixing with the gaseous mixture coming from the main condenser a. A tap, cook, or other air valve may be used instead of the stopper p.

In the arrangement illustrated in Fig. 2, the stopper 3) is replaced by a valve 8 which is arranged to work automatically. This valve is spring controlled, the tension of the spring r being regulated in such a manner that when the pressure exerted on the upper part of the valve 8 decreases below a certain value, air is sucked into the plant through the openings t, which air mixes with the gaseous fluid extracted fromthe main condenser a.

It is not absolutely necessary that the supplementary gaseous fluid shall be air, as any other gaseous fluid may be used instead, for instance, additional steam may be employed, in which case, the steam should be added beyond the auxiliary condenser, so that this steam shall reach the second ejector without fail.

Referring to the arrangement illustrated in Fig. 3, the valve 8 is arranged to admit an additional supply of steam, such steam being drawn from the outlet of the first ejector, which in this case must be sufliciently powerful to supply the necessary quantity of The variation of the pressmall. The lower end of the stem a which is of substantial thickness and is maintained on its seat by a spring 1* is under the action of According atmospheric pressure. It will thus be seen that when the pressure exerted on the upper side of the valve decreases below the value for which the spring 1' is adjusted, the valve will lift and allow the steam coming from the first ejector, and which is not condensed as it does not pass through the auxiliary condenser 2', to enter into the second ejector, and mix with the gaseous fluid extracted from the condenser a.

It is to be understood that the shape of the means provided for the admission .of additional gaseous fluid, shown in Figs. 1, 2 and 3, by way of example, may be Varied.

The additional air or steam may be de rived from any source, provided it comes from a medium in which thepressure is higher than that existing in the described apparatus, at the point of introduction. Thus, the air need not come directly from the atmosphere, but from a receptacle in which it is desired to maintain a decreased vacuum, and the steam may be derived from another source than from the outlet of the first ejector. However, in no case can the gaseous fluid be derived from the condenser from which the first ejector draws, as its addition must be effected in a region of the apparatus where the pressure is higher than that existing in the condenser.

The additional gaseous mass, which in order not to have a disadvantageous effect upon the vacuum of the condenser must be introduced in a region where the mixture extracted from the condenser has already been subjected to a certain amount of compression, exerts its stabilizing action by completing the volume of gas which is required in order that the ejected stream shall during 'its passage fill up the neck, viz., the part of reduced section of the second ejector. It thus follows that the region of introduction of the supplementary mass of gas may be chosen at will between the end of the jet nozzle which supplies the first ejector with working steam and the neck of the second ejector.

The arrangement comprising two steam ejectors in series, an intermediate auxiliary condenser, and means for the addition of a supplementary amount of gaseous fluid, which means form the object of the present invention, may be combined with other ejectors, other auxiliary condensers, and be employed together in the form of a more complex plant.

The extracting devices hereinbefore re ferred to may be employed for extracting gases from a steam condenser, or from any other receptacle.

What I claim is 1. A plant for extracting gases from a receptacle, comprising in combination with a first and a second steam ejector arranged in series with each other and an intermediate auxiliary condenser, additional means for increasing the mass of gas delivered to the second ejector, the inlet of the said means for introducing the supplementary amount of gaseous fluid necessary for this increase being situated at a point Where the gases extracted from the receptacle have already been subjected to a certain amount of com pression.

2. A plant for extracting gases from a receptacle comprising in combination with a first and a second steam ejector arranged in series With each other and an intermediate auxiliary condenser, a member for the automatic admission of supplementary gaseous fluid, in order to increase the gaseous mass delivered to the second ejector, the inlet of the said member for introducing the supplementary amount of gaseous fluid necessary for this increase being situated at a point Where the gases extracted from the receptacle have already been subjected to a certain amount of compression.

3. A condensation plant, comprising in combination with a condenser and an air extracting device consisting of a first and a second steam ejector arranged in series with each other and an intermediate auxiliary condenser, means added to said air extracting device for increasing the gaseous mass supplied to the second ejector, the inlet of the said means for introducing the supplementary amount of gaseous fluid necessary for this increase being situated at a point Where the gases extracted from the receptacle have already been subjected to a certain amount of compression.

4. A condensation plant comprising in combination with a condenser and an air extracting device consisting of a first and a second steam ejector arranged in series With each other and an intermediate auxiliary condenser, a member added to the said air extracting device for automatically admitting a supplementary amount of gaseous fluid, in order to increase the gaseous mass supplied to the second ejector, the in let of the said member for introducing the supplementary amount of gaseous fluid necessary for this increase being situated at a point Where the gases extracted from the' receptacle have already been subjected to a certam amount of compression.

In Witness whereof I have hereunto set my hand in the presence of tWo Witnesses.

MAURICE DELAPORTE.

Witnesses:

HANSON C. Goxn, ALFRED FBEY. 

